The present invention relates to the etching of features into different materials in plasma processing chambers. The present invention also relates to deep silicon etching.
Typically, materials etched in plasma reactors include conductive layers and dielectric layers. Conductive layers may be composed of, for example, metal-containing layers or silicon-containing layers. Dielectric layers may be composed of, for example, organic materials or inorganic materials.
Typically, a particular material is etched in a dedicated etch chamber. That is, dielectric layers are typically etched in dedicated dielectric etch chambers, silicon-containing layers are typically etched in conductor etch chambers, and metal-containing layers are typically etched in metal etch chambers.
Deep silicon etching based on the Bosch process originally developed by Robert Bosch GmbH involves fast switching between silicon etching and polymer deposition for silicon sidewall protection. SF6 and C4F8 are the principal process gasses for the etch and deposition (passivation) cycles, respectively.